Yuichi SARAYA - Academia.edu (original) (raw)
Papers by Yuichi SARAYA
Commissioning of scanning system on rotating gantry at NIRS-HIMAC
Nuclear Instruments and Methods in Physics Research, 2014
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is, however, a crucial issue. The control of the radiation dose and the long exposure time are also problems to be solved. We have developed a prototype system for proton CT with a silicon strip detector and performed a beam test for imaging. The distribution of the electron density has been measured precisely. We also demonstrated an improvement in spatial resolution by reconstructing the proton trajectory. A spatial resolution of 0.45 mm is achieved for a 25-mm-thick polyethylene object. This will be a useful result for upgrading proton CT application for practical use.
Commissioning of moving target irradiation with a scanned carbon-ion beams in NIRS-HIMAC
In moving target irradiation with a scanned ion beam, the interplay effect between the target mot... more In moving target irradiation with a scanned ion beam, the interplay effect between the target motion and scanned beams is a major and well-known problem, which can result in over or under dosage in the target volume. To overcome this problem, we developed fast scanning irradiation system with gating system for moving target. We started the treatment of a moving target by scanning irradiation to the first patient as a clinical study on March 4, 2015. In our presentation, the commissioning of moving target irradiation with pencil beam scanning are reported. To ensure the validity of both the delivered dose and the gating system, patient-specific quality assurance (QA) for moving target irradiation requires an additional procedure. We describe a new patient-specific QA procedure for moving target irradiation and experience with patient-specific QA.The 55th Annual Conference of the Particle Therapy Co-operative Group (PTCOG55
Commissioning of the full energy scanning with carbon-ion beams ranging from 55.6 to 430 MeV/u in NIRS-HIMAC
Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 at the Heavy I... more Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 at the Heavy Ion Medical Accelerator in Chiba (HIMAC). At present, for depth direction, the hybrid depth scanning method has been employed, in which 11 beam energies ranging from 140 to 430 MeV/u are used in conjunction with the range shifter. To suppress the beam spread due the multiple scattering and the nuclear reaction, we have developed a full energy scanning method (FES). In FES, we prepared more than 200 energy steps with 1 or 2 mm intervals. To obtain the range of less than 1 mm without using an energy absorber such as a range shifter, the minimum energy is chosen as 55.6 MeV/u. Generally, a long time is required for accelerator tuning and beam commissioning tests for treatment by FES. In our presentation, we introduce the beam commissioning for FES in a short period of time and the performance of FES is evaluated.The 55th Annual Conference of the Particle Therapy Co-operative Group (PTCOG55
Characteristic of the range verification system using scintillator and CCD camera system
It is essential to consider large-angle scattered particles in dose calculation models for therap... more It is essential to consider large-angle scattered particles in dose calculation models for therapeutic ion beams. However, it is difficult to measure the small dose contribution from large-angle scattered particles. Therefore, we developed a parallel-plate ionization chamber consisting of concentric electrodes (ICCE) to efficiently and easily detect small contributions. The ICCE consists of two successive ICs with a common HV plate. The former is a large plane-parallel IC to measure dose distribution integrated over the whole plane, the latter is a 24-channel parallel-plate IC with concentric electrodes to derive the characteristic parameters describing the lateral beam spread. The aim of this study is to evaluate the performance of the ICCE. By taking advantage of the characteristic of ICCE, we studied the recombination associated with lateral beam profile. Also, we measured a carbon pencil beam in several different media by using ICCE. As a result, we confirmed the ICCE could be u...
For the daily QA of the energy scanning delivery, quick and easy range verification system is req... more For the daily QA of the energy scanning delivery, quick and easy range verification system is required. In this work, we have developed range verification system using scintillator and CCD (charge-coupled device) camera. From the comparison of the several methods, edge detection method is best for range detection. Accuracy of range detection for the system is within the 0.2 mm. Reproducibility of the range is within 0.1 mm. Our range check system has shown to be capable of quick and easy range verification with sufficient accuracy.
SU-F-J-190: Time Resolved Range Measurement System Using Scintillator and CCD Camera for the Slow Beam Extraction
Medical Physics, 2016
PURPOSE To investigate the time structure of the range, we have verified the rang shift due to th... more PURPOSE To investigate the time structure of the range, we have verified the rang shift due to the betatron tune shift with several synchrotron parameters. METHODS A cylindrical plastic scintillator block and a CCD camera were installed on the black box. Using image processing, the range was determined the 80 percent of distal dose of the depth light distribution. The root mean square error of the range measurement using the scintillator and CCD system is about 0.2 mm. Range measurement was performed at interval of 170 msec. The chromaticity of the synchrotron was changed in the range of plus or minus 1% from reference chromaticity in this study. All of the particle inside the synchrotron ring were extracted with the output beam intensity 1.8×108 and 5.0×107 particle per sec. RESULTS The time strictures of the range were changed by changing of the chromaticity. The reproducibility of the measurement was sufficient to observe the time structures of the range. The range shift was depending on the number of the residual particle inside the synchrotron ring. CONCLUSION In slow beam extraction for scanned carbon-ion therapy, the range shift is undesirable because it causes the dose uncertainty in the target. We introduced the time-resolved range measurement using scintillator and CCD system. The scintillator and CCD system have enabled to verify the range shift with sufficient spatial resolution and reproducibility.
High rate silicon tracker for proton computed tomography
2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2014
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements and in-situ positioning can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is saved by reconstructing the proton trajectory. We have developed a prototype system for proton CT and demonstrate a precise measurement of electron density and an improvement in spatial resolution. In order to control of the radiation dose and reduce the exposure time for imaging, the precise position detector should work with very high rate (a few MHz). We have developed high speed tracker with large area silicon strip detector, Amplifier-Shaper-Discriminator LSI, which was developed for drift chamber readout at high energy physics experiment, and FPGA. We report the performance of the tracker evaluated with very high intensity proton beam for the cancer therapy.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2014
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is, however, a crucial issue. The control of the radiation dose and the long exposure time are also problems to be solved. We have developed a prototype system for proton CT with a silicon strip detector and performed a beam test for imaging. The distribution of the electron density has been measured precisely. We also demonstrated an improvement in spatial resolution by reconstructing the proton trajectory. A spatial resolution of 0.45 mm is achieved for a 25-mm-thick polyethylene object. This will be a useful result for upgrading proton CT application for practical use.
High rate silicon tracker for proton computed tomography
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements and in-situ positioning can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is saved by reconstructing the proton trajectory. We have developed a prototype system for proton CT and demonstrate a precise measurement of electron density and an improvement in spatial resolution. In order to control of the radiation dose and reduce the exposure time for imaging, the precise position detector should work with very high rate (a few MHz). We have developed high speed tracker with large area silicon strip detector, Amplifier-Shaper-Discriminator LSI, which was developed for drift chamber readout at high energy physics experiment, and FPGA. We report the performance of the tracker evaluated with very high intensity proton beam for the cancer therapy.
Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 in NIRS-HIMAC.... more Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 in NIRS-HIMAC. Beam delivery system and treatment planning software (TPS) require dosimetric patient-specific QA to check each individual plan. Any change in the scanned beams will result in a significant impact on the irradiation dose. Therefore, patient-specific QA for moving target irradiation requires additional procedure. In an additional QA for moving target irradiation, we placed 2D ionization chamber on the PMMA plate tilted with respect to the beam axis. The PMMA plate was set on the stage of the moving phantom. The moving phantom was moved according to patient data. We measured the dose distribution for both the static target and the moving target. We compared the results for the moving target with those for the static targets by means of a gamma index analysis. In the additional patient-specific QA, the gamma analysis between the moving and static targets showed the good agreement. We confi...
Commissioning of rotating gantry and scanning system at NIRS-HIMAC
Study of spatial resolution and electron density measurement for proton computed tomography
A superconducting rotating-gantry for carbon therapy is being developed. This isocentric rotating... more A superconducting rotating-gantry for carbon therapy is being developed. This isocentric rotating gantry can transport carbon ions with the maximum energy of 430 MeV/u to an isocenter with irradiation angles of over ±180 degrees, and is further capable of performing threedimensional raster-scanning irradiation. The combinedfunction superconducting magnets were employed for the rotating gantry. The superconducting magnets with optimized beam optics allowed a compact gantry design with a large scan size at the isocenter; the length and the radius of the gantry are approximately 13 and 5.5 m, respectively, which are comparable to those for the existing proton gantries. A construction and installation of the superconducting gantry is in progress, and beam commissioning will begin from this autumn. We will report an overview as well as a present status of the superconducting rotatinggantry.
A superconducting rotating-gantry for carbon-ion radiotherapy (CIRT) was developed. This isocentr... more A superconducting rotating-gantry for carbon-ion radiotherapy (CIRT) was developed. This isocentric rotating gantry can transport carbon ions having the maximum kinetic energy of E=430 MeV/u to an isocenter with irradiation angles of over ±180 degrees, and is further capable of performing fast three-dimensional rasterscanning irradiation. By using combined-function superconducting magnets, we could design a compact rotating gantry for CIRT. Construction of the gantry structure as well as the superconducting magnets began since 2013, and installation of the entire rotating-gantry system to the new treatment facility at the National Institute of Radiological Sciences (NIRS) was completed by the end of September, 2015. Beam commissioning subsequently began since October, 2015. After series of the beam commissioning, treatment using the rotating gantry was started since May 2017. We will present an overview of the development for the superconducting rotatinggantry.
As part of the Kanagawa “Challenge-10-years strategy to cancer” it was decided in March 2005 to e... more As part of the Kanagawa “Challenge-10-years strategy to cancer” it was decided in March 2005 to establish a carbon-ion therapy system at the Kanagawa Cancer Center (KCC). From around 2009, the basic design and the foundational planning of the facility were considered and in January 2012 a contract was made with the Toshiba Corp. In December of the same year, the construction of the main building for the acceleration and treatment devices was started and completed in October 2014. Currently, the KCC is in a commissioning phase with the aim to start treatment in December of this year. Various treatments for cancer, which include the present photon LINAC for the radiation therapy, will be provided to patients in cooperation with our cancer center hospital. In addition, we will combine a compact dissemination treatment system of carbon-ion therapy to the pencil beam 3D scanning technique designed by the National Institute of Radiological Sciences (NIRS). The treatment experience with th...
Retraction notice to "Beam position alignment and its verification for therapeutic ion beams from synchrotron" [NIM B 406PA (2017) 368–373]
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Experimental verification of short-range low-energy carbon-ion scanning in NIRS-HIMAC
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Abstract Three-dimensional (3D) pencil-beam scanning is an ideal irradiation technique to make th... more Abstract Three-dimensional (3D) pencil-beam scanning is an ideal irradiation technique to make the best use of the characteristics of a carbon-ion beam and to provide flexible dose delivery. To suppress beam spread due to multiple scattering and nuclear reactions, we developed a full energy scanning method. In some cases, such as eye treatments, the irradiation fields are very small and short ranged. Accordingly, we prepared a minimum low-energy carbon-ion beam corresponding to water-equivalent residual ranges of less than 2 mm. We performed experimental verification for low-energy carbon-ion beams ranging from 55.6 to 96.0 MeV/u. The accuracy of 3D dose delivery with the low-energy carbon-ion beam was verified by measuring the dose distributions for different target volumes. The results confirmed that the measured dose distributions agree well with the calculated ones. Then, the first eye treatment with low-energy carbon-ion beam to a patient was performed in 2018.
Experimental verification of beam switching operation for multiple-ion therapy applications at HIMAC
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Abstract A study of multiple-ion therapy with charged heavy-ion beams was performed to improve ou... more Abstract A study of multiple-ion therapy with charged heavy-ion beams was performed to improve outcomes of refractory cancer treatments. We proposed the accelerator operation method for applying the multiple-ion therapy, to quickly switch the ion species and energies of the output beams. In this method, the irradiation ion species can be changed only by switching the selected ion source and the injector parameters, and the output beam energies can be varied without changing the magnetic operation patterns of the synchrotron. We verified the effectiveness of our approach by conducting experiments at the Heavy Ion Medical Accelerator in Chiba (HIMAC) and confirmed that the approach can provide the fast switching of both the ion species and the beam energies. The experimental results also demonstrated that our approach will greatly reduce the commissioning time and the routine adjustments for multiple-ion beams.
Commissioning of scanning system on rotating gantry at NIRS-HIMAC
Nuclear Instruments and Methods in Physics Research, 2014
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is, however, a crucial issue. The control of the radiation dose and the long exposure time are also problems to be solved. We have developed a prototype system for proton CT with a silicon strip detector and performed a beam test for imaging. The distribution of the electron density has been measured precisely. We also demonstrated an improvement in spatial resolution by reconstructing the proton trajectory. A spatial resolution of 0.45 mm is achieved for a 25-mm-thick polyethylene object. This will be a useful result for upgrading proton CT application for practical use.
Commissioning of moving target irradiation with a scanned carbon-ion beams in NIRS-HIMAC
In moving target irradiation with a scanned ion beam, the interplay effect between the target mot... more In moving target irradiation with a scanned ion beam, the interplay effect between the target motion and scanned beams is a major and well-known problem, which can result in over or under dosage in the target volume. To overcome this problem, we developed fast scanning irradiation system with gating system for moving target. We started the treatment of a moving target by scanning irradiation to the first patient as a clinical study on March 4, 2015. In our presentation, the commissioning of moving target irradiation with pencil beam scanning are reported. To ensure the validity of both the delivered dose and the gating system, patient-specific quality assurance (QA) for moving target irradiation requires an additional procedure. We describe a new patient-specific QA procedure for moving target irradiation and experience with patient-specific QA.The 55th Annual Conference of the Particle Therapy Co-operative Group (PTCOG55
Commissioning of the full energy scanning with carbon-ion beams ranging from 55.6 to 430 MeV/u in NIRS-HIMAC
Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 at the Heavy I... more Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 at the Heavy Ion Medical Accelerator in Chiba (HIMAC). At present, for depth direction, the hybrid depth scanning method has been employed, in which 11 beam energies ranging from 140 to 430 MeV/u are used in conjunction with the range shifter. To suppress the beam spread due the multiple scattering and the nuclear reaction, we have developed a full energy scanning method (FES). In FES, we prepared more than 200 energy steps with 1 or 2 mm intervals. To obtain the range of less than 1 mm without using an energy absorber such as a range shifter, the minimum energy is chosen as 55.6 MeV/u. Generally, a long time is required for accelerator tuning and beam commissioning tests for treatment by FES. In our presentation, we introduce the beam commissioning for FES in a short period of time and the performance of FES is evaluated.The 55th Annual Conference of the Particle Therapy Co-operative Group (PTCOG55
Characteristic of the range verification system using scintillator and CCD camera system
It is essential to consider large-angle scattered particles in dose calculation models for therap... more It is essential to consider large-angle scattered particles in dose calculation models for therapeutic ion beams. However, it is difficult to measure the small dose contribution from large-angle scattered particles. Therefore, we developed a parallel-plate ionization chamber consisting of concentric electrodes (ICCE) to efficiently and easily detect small contributions. The ICCE consists of two successive ICs with a common HV plate. The former is a large plane-parallel IC to measure dose distribution integrated over the whole plane, the latter is a 24-channel parallel-plate IC with concentric electrodes to derive the characteristic parameters describing the lateral beam spread. The aim of this study is to evaluate the performance of the ICCE. By taking advantage of the characteristic of ICCE, we studied the recombination associated with lateral beam profile. Also, we measured a carbon pencil beam in several different media by using ICCE. As a result, we confirmed the ICCE could be u...
For the daily QA of the energy scanning delivery, quick and easy range verification system is req... more For the daily QA of the energy scanning delivery, quick and easy range verification system is required. In this work, we have developed range verification system using scintillator and CCD (charge-coupled device) camera. From the comparison of the several methods, edge detection method is best for range detection. Accuracy of range detection for the system is within the 0.2 mm. Reproducibility of the range is within 0.1 mm. Our range check system has shown to be capable of quick and easy range verification with sufficient accuracy.
SU-F-J-190: Time Resolved Range Measurement System Using Scintillator and CCD Camera for the Slow Beam Extraction
Medical Physics, 2016
PURPOSE To investigate the time structure of the range, we have verified the rang shift due to th... more PURPOSE To investigate the time structure of the range, we have verified the rang shift due to the betatron tune shift with several synchrotron parameters. METHODS A cylindrical plastic scintillator block and a CCD camera were installed on the black box. Using image processing, the range was determined the 80 percent of distal dose of the depth light distribution. The root mean square error of the range measurement using the scintillator and CCD system is about 0.2 mm. Range measurement was performed at interval of 170 msec. The chromaticity of the synchrotron was changed in the range of plus or minus 1% from reference chromaticity in this study. All of the particle inside the synchrotron ring were extracted with the output beam intensity 1.8×108 and 5.0×107 particle per sec. RESULTS The time strictures of the range were changed by changing of the chromaticity. The reproducibility of the measurement was sufficient to observe the time structures of the range. The range shift was depending on the number of the residual particle inside the synchrotron ring. CONCLUSION In slow beam extraction for scanned carbon-ion therapy, the range shift is undesirable because it causes the dose uncertainty in the target. We introduced the time-resolved range measurement using scintillator and CCD system. The scintillator and CCD system have enabled to verify the range shift with sufficient spatial resolution and reproducibility.
High rate silicon tracker for proton computed tomography
2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2014
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements and in-situ positioning can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is saved by reconstructing the proton trajectory. We have developed a prototype system for proton CT and demonstrate a precise measurement of electron density and an improvement in spatial resolution. In order to control of the radiation dose and reduce the exposure time for imaging, the precise position detector should work with very high rate (a few MHz). We have developed high speed tracker with large area silicon strip detector, Amplifier-Shaper-Discriminator LSI, which was developed for drift chamber readout at high energy physics experiment, and FPGA. We report the performance of the tracker evaluated with very high intensity proton beam for the cancer therapy.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2014
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is, however, a crucial issue. The control of the radiation dose and the long exposure time are also problems to be solved. We have developed a prototype system for proton CT with a silicon strip detector and performed a beam test for imaging. The distribution of the electron density has been measured precisely. We also demonstrated an improvement in spatial resolution by reconstructing the proton trajectory. A spatial resolution of 0.45 mm is achieved for a 25-mm-thick polyethylene object. This will be a useful result for upgrading proton CT application for practical use.
High rate silicon tracker for proton computed tomography
Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrati... more Proton computed tomography (CT) is an imaging technique using a high-energy proton beam penetrating the human body and shows promise for improving the quality of cancer therapy with high-energy particle beams because more accurate electron density distribution measurements and in-situ positioning can be achieved with proton CT. The deterioration of the spatial resolution owing to multiple Coulomb scattering is saved by reconstructing the proton trajectory. We have developed a prototype system for proton CT and demonstrate a precise measurement of electron density and an improvement in spatial resolution. In order to control of the radiation dose and reduce the exposure time for imaging, the precise position detector should work with very high rate (a few MHz). We have developed high speed tracker with large area silicon strip detector, Amplifier-Shaper-Discriminator LSI, which was developed for drift chamber readout at high energy physics experiment, and FPGA. We report the performance of the tracker evaluated with very high intensity proton beam for the cancer therapy.
Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 in NIRS-HIMAC.... more Three-dimensional (3D) pencil-beam scanning technique has been utilized since 2011 in NIRS-HIMAC. Beam delivery system and treatment planning software (TPS) require dosimetric patient-specific QA to check each individual plan. Any change in the scanned beams will result in a significant impact on the irradiation dose. Therefore, patient-specific QA for moving target irradiation requires additional procedure. In an additional QA for moving target irradiation, we placed 2D ionization chamber on the PMMA plate tilted with respect to the beam axis. The PMMA plate was set on the stage of the moving phantom. The moving phantom was moved according to patient data. We measured the dose distribution for both the static target and the moving target. We compared the results for the moving target with those for the static targets by means of a gamma index analysis. In the additional patient-specific QA, the gamma analysis between the moving and static targets showed the good agreement. We confi...
Commissioning of rotating gantry and scanning system at NIRS-HIMAC
Study of spatial resolution and electron density measurement for proton computed tomography
A superconducting rotating-gantry for carbon therapy is being developed. This isocentric rotating... more A superconducting rotating-gantry for carbon therapy is being developed. This isocentric rotating gantry can transport carbon ions with the maximum energy of 430 MeV/u to an isocenter with irradiation angles of over ±180 degrees, and is further capable of performing threedimensional raster-scanning irradiation. The combinedfunction superconducting magnets were employed for the rotating gantry. The superconducting magnets with optimized beam optics allowed a compact gantry design with a large scan size at the isocenter; the length and the radius of the gantry are approximately 13 and 5.5 m, respectively, which are comparable to those for the existing proton gantries. A construction and installation of the superconducting gantry is in progress, and beam commissioning will begin from this autumn. We will report an overview as well as a present status of the superconducting rotatinggantry.
A superconducting rotating-gantry for carbon-ion radiotherapy (CIRT) was developed. This isocentr... more A superconducting rotating-gantry for carbon-ion radiotherapy (CIRT) was developed. This isocentric rotating gantry can transport carbon ions having the maximum kinetic energy of E=430 MeV/u to an isocenter with irradiation angles of over ±180 degrees, and is further capable of performing fast three-dimensional rasterscanning irradiation. By using combined-function superconducting magnets, we could design a compact rotating gantry for CIRT. Construction of the gantry structure as well as the superconducting magnets began since 2013, and installation of the entire rotating-gantry system to the new treatment facility at the National Institute of Radiological Sciences (NIRS) was completed by the end of September, 2015. Beam commissioning subsequently began since October, 2015. After series of the beam commissioning, treatment using the rotating gantry was started since May 2017. We will present an overview of the development for the superconducting rotatinggantry.
As part of the Kanagawa “Challenge-10-years strategy to cancer” it was decided in March 2005 to e... more As part of the Kanagawa “Challenge-10-years strategy to cancer” it was decided in March 2005 to establish a carbon-ion therapy system at the Kanagawa Cancer Center (KCC). From around 2009, the basic design and the foundational planning of the facility were considered and in January 2012 a contract was made with the Toshiba Corp. In December of the same year, the construction of the main building for the acceleration and treatment devices was started and completed in October 2014. Currently, the KCC is in a commissioning phase with the aim to start treatment in December of this year. Various treatments for cancer, which include the present photon LINAC for the radiation therapy, will be provided to patients in cooperation with our cancer center hospital. In addition, we will combine a compact dissemination treatment system of carbon-ion therapy to the pencil beam 3D scanning technique designed by the National Institute of Radiological Sciences (NIRS). The treatment experience with th...
Retraction notice to "Beam position alignment and its verification for therapeutic ion beams from synchrotron" [NIM B 406PA (2017) 368–373]
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Experimental verification of short-range low-energy carbon-ion scanning in NIRS-HIMAC
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Abstract Three-dimensional (3D) pencil-beam scanning is an ideal irradiation technique to make th... more Abstract Three-dimensional (3D) pencil-beam scanning is an ideal irradiation technique to make the best use of the characteristics of a carbon-ion beam and to provide flexible dose delivery. To suppress beam spread due to multiple scattering and nuclear reactions, we developed a full energy scanning method. In some cases, such as eye treatments, the irradiation fields are very small and short ranged. Accordingly, we prepared a minimum low-energy carbon-ion beam corresponding to water-equivalent residual ranges of less than 2 mm. We performed experimental verification for low-energy carbon-ion beams ranging from 55.6 to 96.0 MeV/u. The accuracy of 3D dose delivery with the low-energy carbon-ion beam was verified by measuring the dose distributions for different target volumes. The results confirmed that the measured dose distributions agree well with the calculated ones. Then, the first eye treatment with low-energy carbon-ion beam to a patient was performed in 2018.
Experimental verification of beam switching operation for multiple-ion therapy applications at HIMAC
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Abstract A study of multiple-ion therapy with charged heavy-ion beams was performed to improve ou... more Abstract A study of multiple-ion therapy with charged heavy-ion beams was performed to improve outcomes of refractory cancer treatments. We proposed the accelerator operation method for applying the multiple-ion therapy, to quickly switch the ion species and energies of the output beams. In this method, the irradiation ion species can be changed only by switching the selected ion source and the injector parameters, and the output beam energies can be varied without changing the magnetic operation patterns of the synchrotron. We verified the effectiveness of our approach by conducting experiments at the Heavy Ion Medical Accelerator in Chiba (HIMAC) and confirmed that the approach can provide the fast switching of both the ion species and the beam energies. The experimental results also demonstrated that our approach will greatly reduce the commissioning time and the routine adjustments for multiple-ion beams.